Chemical ozone loss in the Arctic and Antarctic stratosphere between 1992 and 2005 (original) (raw)

Ozone depletion in the lower polar stratosphere is strongly dependent on the the amount of chlorine activation that is controlled by polar stratospheric cloud (PSC) occurrence and thus by temperature. We define a new measure, the PSC formation potential (PFP), suitable for assessing ozone depletion in both polar regions. In contrast to the previously defined volume of possible PSC existence (V PSC), this measure is normalized by the vortex volume in accordance with loss in column ozone averaged over the polar vortex and includes the lifetime of the vortices. Chemical ozone loss, derived between 1991 and 2005 for Arctic and Antarctic winters, correlates well with the PFP in the Arctic. In the Antarctic, chemical ozone loss is saturated. The year-to-year variation of the PFP for the Arctic has risen over the past thirty years with a maximum value in winter 2005. Accordingly, maximum chemical ozone loss has reached Antarctic loss values.